1. Field of the Invention
The present invention relates to a hydraulic hinge, especially for a hydraulic hinge for a glass door.
2. Description of Related Art
A glass door is pivotally mounted on a doorframe by a hydraulic hinge. A conventional hydraulic hinge has a fixing plate, a rotating seat, a pivot and a buffer module. The fixing plate is mounted on the doorframe. The rotating seat is mounted on the glass door and has an oil chamber for storing oil and an oil passage communicating with the oil chamber. The pivot has a first portion, a second portion and an eccentric cam. The first portion of the pivot is mounted on the fixing plate and the second portion of the pivot is mounted into the rotating seat. The eccentric cam is located in the rotating seat. The buffer module is mounted on the rotating seat and is located in the oil chamber of the rotating seat. The buffer module has a valve and a spring. The valve has a through hole for receiving the pivot and a fixing element for abutting against the eccentric cam. The valve has a recess communicating with the through hole and the oil passage, a first oil hole and a second oil hole. The first oil hole and the second oil hole communicate with the recess and the oil chamber. The spring abuts against the rotating seat and the valve.
When the glass door is pivoted, the rotating seat is rotated relative to the fixing plate. The eccentric cam of the pivot abuts the fixing element of the valve for controlling the valve to press the spring and drive oil in the oil chamber. However, the valve is structurally complex, thereby complicating the manufacturing process. Additionally, the rotating seat provides only a single oil passage, so the glass door is closed slowly such that cool air generated by an air-conditioner escapes from the house.
To overcome the shortcomings, the present invention provides a hydraulic hinge to mitigate or obviate the aforementioned problems.